-LRB- CNN -RRB- -- After President Obama announced his support for same-sex marriage , a group organizing a fundraiser on his behalf suddenly had to find a bigger venue . The event , featuring the pop singer Pink , is one of two LGBT-organized fundraisers Obama is expected to attend on the West Coast on Wednesday .

A CNN analysis of President Obama 's biggest fundraisers , known as bundlers , shows that at least 33 -- or about one in every 16 bundlers -- is openly gay . Together , they have raised at least $ 8 million for the campaign between January and the end of March .

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By contrast , in the same period , bundlers from the television , movie and music industry , some of whom attended a recent high-profile fundraiser hosted by actor George Clooney , raised $ 6.8 million , according to the Center for Responsive Politics .

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While campaign finance laws require donors to disclose their full names , addresses , occupations and employers , there is no box to check for sexual orientation . Nor does the law require candidates to release information about their bundlers . Under prodding from watchdog groups , presidential campaigns have released bundler data in past elections . Obama 's campaign has released its list . Republican candidate Mitt Romney 's campaign has not .

In CNN 's analysis , only bundlers who have disclosed their orientation in past CNN reporting or in trusted LGBT publications were counted as gay . The Washington Post has reported that as many as one in six bundlers supporting Obama are gay . The Advocate Magazine estimates one in five .

Glancing down the names on the bundlers list released by the Obama campaign for the first quarter , it is easy to find people known for their work on behalf of the LGBT community .

Tim Gill , a software entrepreneur who runs a large Colorado-based foundation that backs gay rights projects , has already contributed $ 672,800 with his partner Scott Miller to the Obama for America campaign . Fred Eychaner , who owns the Chicago-based Newsweb Corp. , has donated $ 1,220,550 so far .

He co-hosted a $ 35,800-per-person LGBT organized fundraiser for Obama in February . Kathy Levinson , the former president and CEO of the Menlo Park , California-based Etrade , gave $ 202,150 . The LA Gay and Lesbian Center Women 's Night named Levinson a `` Community Role Model '' in 2000 . She was instrumental in raising money to stop the anti-same-sex marriage law in California .

Donations made after Obama announced his support for same-sex marriage May 9 wo n't be released until mid-June , when the campaign files its second-quarter reports with the Federal Election Commission .

Many LGBT bundlers have maintained a close relationship with the president throughout his first term . A state dinner in March was attended by bundlers Gill ; Eychaner ; Barry Karas , a former Human Rights Campaign board member ; James -LRB- Wally -RRB- Brewster , senior vice president of General Growth Properties , a real estate investment trust that owns and operates shopping malls ; Dana Perlman , a corporate lawyer who has served as co-chair of the Obama/DNC LGBT Leadership Council ; Joseph Falk , a Miami mortgage broker and others .

Support for Obama from the LGBT community was challenged after the initial excitement of his first campaign , largely because of what was perceived as his lukewarm support on same-sex marriage . Some say a low point came during the election in 2008 , when evangelist pastor Rick Warren asked Obama how he defined marriage and he called it `` a union between a man and a woman . '' He added : `` For me as a Christian , it is a sacred union . God 's in the mix . '' He further angered the community by picking Warren to deliver his invocation at the presidential inauguration .

Actor Alan Cumming wrote in 2010 , `` We keep hearing that Obama is an ally , that DADT -LSB- the ` do n't ask , do n't tell ' policy that kept LGBT people from openly serving in the military -RSB- will end under his watch , but what do we actually get ? Diddly squat . ''

Dustin Lance Black , who won a best screenplay Oscar for `` Milk , '' a movie biography of the gay San Francisco politician Harvey Milk who was gunned down because of his sexual orientation , said last year that he had been an Obama supporter before but might sit out the upcoming election . When President Obama finally signed the repeal of `` do n't ask , do n't tell '' and `` evolved '' in his position on marriage by saying he was in favor of it for the LGBT community , both Black and Cumming did more than just say they supported the president . They donated money . They also encouraged others to do the same .

David Mixner , who started one of the first LGBT-themed PACs in the late 1970s , said the community has come a long way in being accepted in electoral politics . `` We had some candidates who would n't take our money back then because they did n't want to be associated with anyone who was gay , '' Mixner said . He said he believes that changed with the Clinton administration , which the PAC raised $ 4 million to support . `` Now the community knows how to raise money and contribute on their own and we are more than welcome at the table . ''

The LGBT community is such an important part of this president 's re-election effort that the Obama for America campaign hosts a special section for it on its website . It includes a video discussing the president 's support for LGBT issues narrated by actress Jane Lynch , who is openly gay . It also offers Obama merchandise like T-shirts and drink koozies to bring to Gay Pride events this summer .

The president has already attended several LGBT-organized fundraisers , including one in New York hosted by openly gay singer Ricky Martin , the Futuro Fund , and Obama for America LGBT Leadership Council .

Another event in Washington , hosted by Karen K. Dixon and her partner , Dr. Nan Schaffer , was rumored to have raised more than a million dollars for the campaign , although the Obama team wo n't comment on the record about fundraising . Tickets for one of the California events were selling so well the campaign had to find a larger venue . There also is great interest in a Chicago fundraiser co-hosted by LGBT bundlers Brewster and Bob Satawake . The couple has already raised $ 288,663 , according to the CNN analysis .

`` I think there has always been a strong base of support from LGBT people for the president , '' said Michael Cole-Schwartz , spokesperson for the Human Rights Campaign , whose incoming president Chad Griffin is a bundler . `` He earned even more respect from the community -- from repealing ` do n't ask , do n't tell , ' to signing the hate crimes law giving the first civil rights protection for us in federal law , to coming out against DOMA , '' the Defense of Marriage Act that defines marriage for federal purposes as unions exclusively between a man and a woman . `` Now , with his saying he believes in full marriage equality , we have another reason for people in our community to be generous with their time and money . ''

It is difficult to know if there are any openly gay bundlers for the Republicans , because Romney has not disclosed his bundler list .

The Republican candidate has , however , voiced his opposition to civil unions and supports a federal amendment to the U.S. Constitution to deny same-sex couples the right to marry .

But some gay Republicans say Romney is not totally close minded on LGBT issues . `` On gay issues , where Romney stands is not as black and white as it seems , '' said R. Clarke Cooper , executive director of the Log Cabin Republicans , an organization for gay and lesbian Republicans . `` One thing he has been consistent on , as governor and as a candidate for president , is he has spoken in broad terms about ending discrimination in the workplace . He has said there is no room for it . ''

Cooper said the Log Cabin Republicans have n't decided yet if they will endorse Romney . That announcement will come sometime this fall . He does believe , though , that there are gay donors to Romney 's campaign . They just might not be as outspoken .

`` We joke that at Pride -LRB- festivals -RRB- , the question we most often ask other Republicans we see there is , ` Are you out ? ' Meaning ` out ' about your politics yet . ''

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A CNN analysis of Obama 's biggest fundraisers shows about one in every 16 is openly gay

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Gay fundraisers have raised more than $ 8 million for the Obama campaign

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Similar figures are not available for the Romney campaign